An overlay network may mean a virtual network configured over a physical network.
FIG. 1 is a conceptual view to explain a general system for providing an overlay network. Referring to FIG. 1, an overlay technology supporting configuration of an overlay network utilizes a network virtualization authority (NVA) 100 and a network virtualization edges (NVE) 210 and 220 in order to configure a virtual network.
Specifically, a total configuration of the network virtualization based on overlay is managed by the NVA 100, and the NVE 210 may receive information for overlay configuration from the NVA 100, and perform overlay functions such as encapsulation and decapsulation based on the information.
The NVEs 210 and 220, located in respective data centers (DC), are connected to a plurality of tenant systems (TS) 500, and the TSs may be elements such as servers, storages, etc.
Meanwhile, according to appearance of software defined networking (SDN) technologies which can flexibly control networks of a telecommunication operator, DC controllers 310 and 320 are responsible for network configuration and control functions within the respective DCs, and the NVEs communicate with the DC controllers 310 and 320 in order to request necessary information.
Also, in order to configure an underlay network located in a wide area network (WAN), a WAN controller 400 is responsible for configuration of network apparatuses 600 in the WAN, and controls functions for them.
However, information on configurations, operations, and statuses related to the underlay network, which are collected by the WAN controller 400, are still not utilized for configuration of the overlay network.
That is, a conventional technology related to the configuration of the overlay network focuses only upon configuration of an overlay network, regardless of available resources, operation statuses of network apparatuses, WAN paths, etc. of the underlay network.
Therefore, since the conventional technology configures an overlay-based virtual network regardless of failures occurring in the underlay network and network usage ratios for respective sections of the underlay network, efficiency of network resource usage cannot be guaranteed, and performance of virtual network also cannot be guaranteed.